1. Field of the Invention
The present invention relates to a film pack and more particularly, to a film pack having light shielding means for use in association with a camera employing film in the form of individual film units.
2. Description of the Prior Art
There is known a photographic process, frequently referred to as `auto-process`, according to which film is provided not in roll form but in the form of individual units each of which comprises at least a negative image layer and a transfer image layer and has associated therewith processing solution contained in breakable pods, which are usually embedded in an edge portion of the film unit. The negative image layer is exposable to form a negative or latent image of an object, and a corresponding, a viewable image may be formed on the transfer image layer under the influence of the processing solution, which is extruded from the pods and spread through the film unit under the action of pressure means between which the film unit is passed subsequent to exposure, which are conveniently provided as processing rolls, for example, mounted inside the associated auto-process camera, and which also act to move film unit to the exterior of the camera, whereby a finished photographic print may be available to a photographer in a very short time after a film unit is exposed, without it being necessary for the photographer to proceed to a separate, specially equipped location for development and processing of film. An autoprocess camera must therefore include a film pack for positioning successive film units at an exposure station, processing rolls or other pressure means for processing exposed film units and moving the film units to the exterior of the camera, and means for forwarding successive film unit from the exposure station to the processing rolls.
Conventionally, such a film pack accommodating the film units therein and releasably attached to the camera body is of a rectangular or square box-like configuration, which film pack must be of light shielding construction, especially at a discharge outlet thereof for delivering the exposed film units out onto the pressure rolls. In other words, the film pack of the above described type should be so constructed that the same is able to shield the film units therein against any outside light prior to attachment of the pack to the camera body and that shielding for an exposure opening and the discharge outlet formed in the pack be released when the pack is mounted in the camera ready for shooting.
Commonly, in the auto-process camera of mirror image type employing the film units of known structure, a light shielding stopper plate is provided at the discharge outlet of the film pack, which stopper plate is adapted to be forcibly opened when the film pack containing the film units therein is attached to the camera body. The conventional film pack of the above described type, however, has such a serious disadvantage that, although light is shielded by a light shielding plate or the like even when the stopper plate is released, there still remains danger of light leakage which may expose part of the film units held in the pack to unnecessary light.
In order to overcome such disadvantages, a light shielding stopper releasing means entitled "A camera having light shielding stopper releasing means for a film pack" was proposed by the Japanese patent application Ser. No. 49-40570, filed on Apr. 9, 1974 by the same assignee, in which application, there is disclosed a light shielding stopper releasing means wherein a light shielding stopper plate for the film unit is provided with projections or bent portions extending outwardly at right angles from the opposite side walls of said stopper palte, which projections are adapted to engage a lever member pivotally mounted on the rear cover plate of the camera, or the camera body and after the film pack with film units accommodated therein has been mounted in the camera body with the rear cover plate of the camera closed, the lever is actuated, by an associated slidable knob provided on the rear cover plate of the camera, for engagement with the projections of the stopper plate and consequently for partially raising the stopper plate so as to open the discharge outlet which is communicated with a corresponding slot formed in the camera body for discharging exposed film units out of the camera through pressing rolls. In this arrangement, the film pack loaded within the camera body is perfectly shielded against outside light prior to actuation of the lever except for exposure during shooting.
Accordingly, an essential object of the present invention is to provide a film pack having light shielding means for use in an auto-process camera which corresponds the technical concept of the light shielding stopper releasing means disclosed in the above Japanese patent application Ser. No. 49-40570, and in which a discharge outlet of a film pack is perfectly covered and shielded against light upon loading the film pack within the camera, while the shielding is readily released by the actuation of releasing means from outside of the camera with substantial elimination of the disadvantages inherent in the conventional film pack.
Another important object of the present invention is to provide a film pack of the above described type which is accurate in functioning and can be readily mounted in the auto-process camera.
A further object of the present invention is to provide a film pack of the above described type which is simple in construction and can be manufactured at low cost.